Imaging techniques using radioactive rays, particularly X-rays, are one of the important techniques employed in the medical fields to acquire internal body images, and X-ray imaging apparatuses use such X-rays.
Conventional X-ray imaging apparatuses using X-rays are put into practice as various types of apparatuses for taking images of all or part of a human body such as internal organs, dental structure and skull.
The conventional X-ray imaging apparatuses are configured to include an X-ray beam generator for emitting and irradiating an X-ray beam on an object, an X-ray beam detector for detecting the X-ray beam that has been irradiated from the X-ray beam generator and then projected on the object placed in the beam path, and an image display unit for displaying the image of the object according to a signal detected in the X-ray beam detector.
Here, the X-ray beam generator and X-ray beam detector are disposed at the locations spaced apart from each other by a predetermined distance. Further, the X-ray beam generator is configured to include an X-ray beam source for emitting the X-ray beam.
One example of the conventional X-ray imaging apparatuses is a dental CT (computed tomography) apparatus, which is an X-ray imaging apparatus used in dental clinics to image teeth and/or skull and provide X-ray images for dental procedures such as orthodontic treatment or maxillary correction. FIG. 1a shows a teeth image taken by the dental CT apparatus and FIG. 1b shows a skull image.
In the X-ray images, facial skin tissues form relatively transparent contours compared to osseous tissues due to the difference in X-ray absorption. The above X-ray imaging apparatuses are used in a variety of fields such as dentistry as mentioned above, as well as plastic surgery. In particular, the field of dentistry or plastic surgery requires not only the above-described X-ray image but also an exterior image of an object, e.g., a face image of a patient for dental correction or plastic surgery.
The exterior image of the object is superimposed with the X-ray image of the corresponding part so that they may be utilized as diagnostic data for the dental correction or plastic surgery and at the same time used to plan the procedures suitable for the patient and simulate a virtual plastic surgery or a virtual correction.
The exterior image of the object needs to be correctly superimposed with the X-ray image of the part corresponding to the exterior image so as to increase accuracy of the diagnostic data. Therefore, the inventors have developed an X-ray imaging apparatus which may increase accuracy of superimposition of an exterior image and an X-ray image of an object and minimize image adjustment procedures for the X-ray image and/or exterior image.